The PNAS study recruited 85 people from Northern Italy who had all been diagnosed with early stage Alzheimer’s. Forty people in the study spoke only Italian, while 45 people spoke Italian and German, both languages learned from an early age (they were recruited from the town of Bolzano, on the Italian – Austrian border).
Bilingual Speakers Use More Brain Regions
There are two interesting results from the study. First, PET brain imaging scans revealed that the bilingual speakers were using significantly more brain regions compared to Italian-only speakers when engaged in study tasks:
The PET imaging results support the concept that “cognitive reserve”, a term used to describe the positive effects of more cognitive abilities like higher education levels and bilingualism, can provide an enhanced ability to resist neurodegenerative conditions like dementia.
A Four to Five year Buffer?
The second important note from the study is that the bilingual speakers were on average five years older than their Italian-only counterparts, but both groups were in the early stages of Alzheimer’s.
The implication here is that the bilingual speakers in the PNAS study had an extra 5 year “buffer” of cognitive health before declining into early stage Alzheimer’s. This brain health benefit is backed up by another study that estimates a 4 year buffer against Alzheimer’s disease from speaking two languages.
Other factors also apply when looking at lifetime risk and protection against Alzheimer’s disease, such as diet choices, exercise patterns, and avoiding or managing chronic diseases. Take the Healthy Brain Test to learn more on how to maintain a healthy brain.